Marilie Gammon

Area of interest

Dr. Gammon's current research focuses on the identification of risk factors related to the incidence and survival of: (1) breast cancer, particularly estrogen-related factors that are potentially modifiable (e.g., physical activity, obesity, and environmental exposures, including polycyclic aromatic hydrocarbons and active and passive cigarette smoking), and (2) esophageal and gastric cancer (by determining the major contributors to disease burden e.g., cigarette smoking, obesity, and GERD). Research efforts include molecular epidemiologic techniques in an effort to elucidate inconsistent or modest effects.

Dr. Gammon is currently principal investigator of the Long Island Breast Cancer Study Project (LIBCSP), a multidisciplinary, multi-institutional collaboration to identify environmental risk factors for the disease. This population-based project includes three major components: a case-control study, a survivorship study, and molecular epidemiologic studies. The LIBCSP case-control study was funded by NCI and NIEHS. The study includes personal interviews with over 3,000 residents of Nassau and Suffolk counties in New York State. Samples of blood and urine were donated by over 2,200 women, and environmental samples of dust, water, and soil were obtained from the homes of nearly 700 long-term residents. Seven manuscripts have been published to date; several others have been submitted or are nearly ready to submit. Analyses of the role of other environmental and modifiable lifestyle factors in breast cancer development are ongoing.

The LIBCSP survivorship study is one of the first to examine the potential influence of environmental factors on breast cancer mortality, and is funded by the NCI and the Lance Armstrong Foundation. Breast cancer case women and/or their next of kin were recontacted to: determine vital status; obtain information on the breast cancer medical treatment undergone (including use of complimentary and alternative medicines); and assess any changes in behavior or environmental exposures that were reported at diagnosis (during the case-control interview). The study also includes retrieval and review of the subjects' medical records. Data analyses are underway.

The LIBCSP molecular epidemiology studies include laboratory assays on the biologic tissues collected as part of the parent case-control study. These include: blood (for measures of pesticides and PAH-DNA adducts); urine (for assays of estrogen metabolites); DNA (for genetic polymorphisms involved in the metabolism of environmental carcinogens and estrogen, oxidatative stress, and DNA repair); and archived tumor tissue (for immunohistochemical staining for p53 protein expression, HER-2/enu overexpression, and cyclin D). These molecular epidemiology studies are funded by over two dozen grants awarded to Dr. Gammon and her colleagues over the past five years; Funding agencies include the U.S. Army, American Cancer Society, Cancer Foundation of America, Breast Cancer Research Foundation, National Institute of Environmental Health Sciences, and the National Cancer Institute. The ongoing analyses are currently focused on the case-control comparisons to identify factors involved in breast cancer incidence; future analyses will focus on survivorship issues among the case women only.

Awards and Honors

In 2001, Dr. Gammon was appointed Deputy Director of the UNC-CH Center for Environmental Health and Susceptibility. In 2003, Dr. Gammon was promoted to Professor in the Department of Epidemiology in the School of Public Health. In 2000, Dr. Gammon was also appointed to the position of Associate Editor for the American Journal of Epidemiology, the premier publication of the discipline's largest professional organization.

In 2002, results of the main hypotheses of the case-control component of the Long Island Breast Cancer Study Project (LIBCSP), examining polycyclic aromatic hydrocarbons and organochlorine levels in blood, along with a detailed description of the case-control study, were published.

In 2003, results on the component of the LIBCSP that examined the potential relation with electromagnetic fields (EMF) were published.

More recent efforts have focused on the role of energetics (weight, weight gain, physical activity and diet) in breast cancer risk and survival. In 2004, we reported our results on fruit and vegetable intake; among those who consumed five or more servings per day were 30% less likely to develop breast cancer. In a recent report published in 2005, we noted that among postmenopausal women those who gain weight after age 50 are more likely to develop breast cancer than those who maintain their weight, regardless of their weight at age 50.